Polyacetal resins are excellent in balance among mechanical properties, thermal properties, electrical properties, sliding properties, moldability and the like and therefore are widely used as structural materials and mechanism elements for electric instruments, automobile parts, precision machinery components and the like. However, they may be sometimes insufficient in mechanical properties such as impact resistance and the like or in heat resistance and may often require further improvements in these properties according to applications.
Conventionally, a polyoxymethylene resin composition is disclosed in which magnesium hydroxide is compounded to a polyoxymethylene resin composition in order to improve heat resistance (see Patent Document 1).